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Most of the GOP material was not released

The intel community has growing confidence the hacking was meant to help Trump

Washington (CNN)Russian hackers breached accounts of GOP individuals and organizations prior to the election -- including GOP House members, thought leaders and non-profits tied to the Republican party -- a former senior law enforcement official with direct knowledge of the investigation told CNN Monday.

Since most of the GOP material was not released, whereas the emails of Democratic Party groups and officials were made public, the intelligence community has growing confidence that hacking of US entities was meant to steer the US election toward Trump.

In addition, there is evidence that entities connected to the Russian government were bankrolling "troll farms" that spread fake news about Clinton, according to the former official.

Investigators also found digital footprints of individuals tied to the Russian government who had been on intelligence agencies' radar before, as was acknowledged when the intelligence agency put out a public statement in October.

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All of these findings provide a greater understanding of what the intelligence community relied on to assess Russia's intentions.

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Even before the election, the US intelligence community was "close" to assessing that Russia's intention was to aid Trump, rather than simply to disrupt the election process, the former senior law enforcement official said.

However, there was disagreement -- particularly between the intelligence agencies and the FBI -- as to how certain this assessment was, multiple officials told CNN.

The former senior law enforcement official made clear Monday that assessing the intentions of a foreign power is imprecise by its nature. Moreover, a separate US official explained that the FBI is very conservative in its conclusions and typically doesn't give any definitive assessment if a conclusion can't be proven without a doubt. The CIA constantly has to make judgments based on an incomplete picture.

However, "Everyone agrees that a foreign power, i.e., Russia, engaged in criminal activity inside the United States," the former official said.